Conventionally, an information system utilized by a plurality of users allocates user identification information, which is identification information (hereinafter referred to as “ID”) for identifying the users, to the respective users of the information system. Thereafter, a server or the like in the information system manages personal information of each user by correlating the personal information of the user with the relevant user ID.
Along with advances in wide area networks such as the Internet in recent years, various services such as e-mail, auctions, or account management in financial institutions are developed through the wide area network.
For example, Japanese Unexamined Patent Publication No. 2002-7937 discloses an authentication mediation system for managing the user ID which are registered individually for various service sites by use of an authentication mediation server (see Patent reference 1).
(Patent Reference 1)
Japanese Unexamined Patent Publication No. 2002-7937 Along with development in the various services, it is desirable that some of the services are made available by use of different ID which is temporarily provided while concealing the user ID. For example, in Japanese unexamined Patent Publication No. 2002-7937, the user may wish not to register the user ID directly with the authentication mediation server of a highly confidential service site such as a financial institution but to register the different ID, which is accessible only to the relevant service site, for the authentication mediation server. Moreover, for example, it is desired to use the different ID while concealing the original user ID when the user requests for a price estimate of merchandise or sends a complaint about the service, and so forth.
In such cases, when the user registers a new different ID which is not related to the user ID at all with the service site, there arise problems that the personal information needs to be registered redundantly, and that an operation performed by using one of the ID is not reflected in the personal information of the other ID. Accordingly, it is desired to provide an identification information managing method which makes an unauthorized server and the like incapable of distinguishing a connection between the user ID and the different ID issued to the same user while maintaining the connection between the user ID and the different ID.